package day20171115;


     class A {
        void f() {
            System.out.println("I am A");
        }
    }
        class B {}

        public class Hello {
            public static void main(String args[])
            {
                System.out.println("你好，很高兴学习java");
                A a = new A();
                a.f();
            }
        }

